Bedrock geology of the Evitts Creek and Pattersons Creek quadrangles, Maryland, Pennsylvania, and West Virginia

Basic Information
Author: De Witt, Wallace, Jr. and Colton, G.W.
Description:Publication and maps of the Evitts Creek and Pattersons Creek quadrangles at a 1 to 24000.The Evitts Creek and Pattersons Creek quadrangles occupy about 115 square miles of mountainous western Maryland and contiguous parts of Pennsylvania and West Virginia. The exposed strata consist of about 8,000 feet of sedimentary rocks ranging in age from Late Ordovician to Late Devonian. The stratigraphic sequence is divided into 21 formations, several of which are subdivided into members. In ascending order the stratigraphic units are: the Juniata Formation of Ordovician age; Tuscarora Quartzite, Rose Hill Formation, Reefer Sandstone, Rochester Shale, McKenzie Formation, Bloomsburg Red Beds, Wills Creek Shale, and Tonoloway Limestone of Silurian age; Keyser Limestone of Silurian and Devonian (?) age; the Helderberg Group (Coeymans Limestone, New Scotland Limestone, and Mandata Formation), Oriskany Group (Shriver Chert and Ridgeley Sandstone), Needmore Shale, Marcellus Shale, Mahantango Formation, Harrell Shale (including the Burket Black Shale Member in the basal part), Woodmont Shale, and Chemung(?) Formation of Devonian age. The hard and resistant formations such as the Juniata Formation, Tuscarora Quartzite, and Ridgeley Sandstone commonly form the large hills and mountains in this region. The soft and easily eroded formations such as the Wills Creek Shale, Needmore Shale, Marcellus Shale, and Harrell Shale generally underlie lowlands and valleys.
Publication Date:
Author Contact Information
Distributor Contact Information
Organization Name: U.S. Geological Survey
Street: 12201 Sunrise Valley Drive
City: Reston
State: VA
Zip: 20192
Phone: 703-648-5953
Geographic Extent
North Bounding Latitude: 40.2813160123
South Bounding Latitude: 37.7204466746
East Bounding Longitude: -76.8022460938
West Bounding Longitude: -78.23046875